1. Statement of the Technical Field
The inventive arrangements relate generally to the field of micro devices, and more particularly to microfluidic control systems.
2. Description of the Related Art
Miniaturization of various devices which incorporate fluidic systems has spurred a need for fluidic systems having very small components. These systems are commonly known as microfluidic systems. Microfluidic systems have the potential to play an increasingly important role in many developing technology areas. For example, there has been an increasing interest in recent years in the use of liquid fuels in microengines and in the use of fluid dielectrics in electronics systems.
Another technological field where micro-fluidic systems are likely to play an increasingly important role is fuel cells. Fuel cells generate electricity and heat by electrochemically combining a fuel and an oxidant, via an ion-conducting electrolyte. Some types of fuel cells produce waste water as a byproduct of the reaction. This waste water must be transported away from the reaction to be exhausted from the system by a fluid management sub-system.
Efforts are currently under way to create very small fuel cells, called microcells. It is anticipated that such microcells may eventually be adapted for use in many portable electronics applications. For example, such devices could be used for powering laptop computers and cell phones. Still, microcells present a number of design challenges that will need to be overcome before these devices can be practically implemented. For example, miniaturized electro-mechanical systems must be developed for controlling the fuel cell reaction, delivering fuel to the reactive components and disposing of water produced in the reaction. In this regard, innovations in fuel cell designs are beginning to look to silicon processing and other techniques from the fields of microelectronics and micro-systems engineering.
As with most other types of fluidic systems, microfluidic systems usually incorporate control valve devices that are implemented as discrete components. Discrete components tend to be bulky, however, which oftentimes impedes miniaturization efforts. Moreover, such control valve devices typically include pluralities of moving parts that must interoperate. The reliability of such devices, however, is generally inversely proportional to the number of moving parts since the moving parts tend to wear. Hence, an embedded control valve that can overcome the aforementioned limitations is needed for use in microfluidic systems.